Circular stapling instruments

ABSTRACT

A surgical system includes an adapter assembly and a tip protector. The adapter assembly includes a tubular housing, and a trocar assembly selectively receivable in the tubular housing. The tip protector includes a housing defining a channel therethrough configured for receipt of the trocar member, a first locking member movably coupled to the housing and configured to selectively engage the trocar member to lock the tip protector to the trocar member, and a second locking member movably coupled to the housing and configured to selectively engage a distal end portion of the tubular housing to lock the tip protector to the tubular housing.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Continuation application of U.S. patentapplication Ser. No. 16/503,857, filed on Jul. 5, 2019 (now U.S. Pat.No. 11,344,309), the entire contents of which being incorporated byreference herein.

BACKGROUND 1. Technical Field

The disclosure relates to surgical devices. More specifically, thedisclosure relates to handheld electromechanical circular staplinginstruments for performing end-to-end anastomosis procedures.

2. Background of Related Art

Circular clamping, cutting and stapling devices may be employed in asurgical procedure to reattach colon portions that were previouslytransected, or to conduct similar procedures. Conventional circularclamping, cutting, and stapling devices include a pistol or lineargrip-styled structure having an elongated shaft extending therefrom anda loading unit portion. The loading unit portion includes an endeffector having a staple cartridge housing a plurality of staplessupported on the distal end of the elongated shaft and an anvil assemblysupported adjacent to the staple cartridge. During the surgicalprocedure, a physician may insert the loading unit portion of thecircular stapling device into a rectum of a patient and maneuver thedevice up the colonic tract of the patient toward the transected colonportions. The anvil assembly can be purse stringed along one of thetransected colon portions. Alternatively, if desired, the anvil assemblycan be inserted into the colon through an incision proximal to thetransected colon portion. Once properly positioned within the transectedcolon portions, the anvil assembly and staple cartridge are approximatedtoward one another and the staples are ejected from the staple cartridgetoward the anvil assembly thereby forming the staples in tissue toaffect an end-to-end anastomosis of the transected colon portions. Anannular knife is fired to core the anastomosed colon portions. After theend-to-end anastomosis has been affected, the circular stapling deviceis removed from the surgical site.

The circular clamping, cutting, and stapling devices may include apowered drive system including a powered handle assembly, which may bereusable, and a disposable end effector that is removably connected tothe powered handle assembly.

Many of existing end effectors for use with existing powered surgicaldevices and/or handle assemblies are driven by a linear driving force.For example, end effectors for performing endo-gastrointestinalanastomosis procedures, end-to-end anastomosis procedures and transverseanastomosis procedures, are actuated by a linear driving force. As such,these end effectors are not compatible with surgical devices and/orhandle assemblies that use a rotary driving force.

In order to make the linear driven end effectors compatible with poweredsurgical devices that use a rotary driving force, adapters are used tointerconnect the linear driven end effectors with the powered rotarydriven surgical devices. These adapters may also be reusable, and assuch, are configured to withstand multiple sterilization cycles. Priorto undergoing a sterilization process, certain components of the adaptermay be removed to allow access of sterilization fluids into areas of theadapter and/or to prevent damage to vulnerable components of theadapter.

SUMMARY

According to one embodiment of the disclosure, an adapter assembly of acircular stapler is provided. The adapter assembly includes a tubularhousing, a trocar assembly selectively receivable in the tubularhousing, a first retention pin supported in the tubular housing, and acamming member associated with the first retention pin. The trocarassembly includes a trocar housing defining a first opening, and atrocar member axially movable within the trocar housing and configuredto support an anvil assembly. The camming member is configured to movethe first retention pin relative to the trocar housing between a firstposition and a second position. In the first position, the firstretention pin is received within the first opening in the trocar housingto lock the trocar assembly with the tubular housing. In the secondposition, the first retention pin is removed from the first opening inthe trocar housing to release the trocar assembly from the tubularhousing.

In aspects, the first retention pin may define a hole and the cammingmember may include a first arm disposed within the hole of the firstretention pin, such that movement of the first arm of the camming membermoves the first retention pin between the first and second positions.

In aspects, the first arm of the camming member may have an obliquesection disposed within the hole of the first retention pin.

In aspects, the first retention pin may have a first camming surface andthe oblique section of the camming member may have a first cammingsurface configured to engage the first camming surface of the firstretention pin upon a downward movement of the camming member to urge thefirst retention pin toward the second position.

In aspects, the first retention pin may have a second camming surfaceand the oblique section of the camming member may have a second cammingsurface configured to engage the second camming surface of the firstretention pin upon upward movement of the camming member to urge thefirst retention pin toward the first position.

In aspects, the first arm of the camming member may have first andsecond longitudinal sections disposed in parallel relation to oneanother. The oblique section may interconnect the first and secondlongitudinal sections and extend inwardly in a direction from the firstlongitudinal section toward the second longitudinal section.

In aspects, the hole of the first retention pin may have a steppedconfiguration.

In aspects, the adapter assembly may further include a button movablycoupled to the tubular housing. The camming member may have a backspandisposed underneath the button, such that a downward movement of thebutton actuates the camming member to move the first retention memberfrom the first position toward the second position.

In aspects, the adapter assembly may further include a biasing memberengaged with the backspan of the camming member and configured toresiliently bias the button toward the first position.

In aspects, the adapter assembly may further include a second retentionpin supported in the tubular housing. The trocar housing may define asecond opening, opposite the first opening in the trocar housing. Thecamming member may have a first arm associated with the first retentionpin and a second arm associated with the second retention pin, such thatan actuation of the camming member moves the first and second retentionpins into the respective first and second openings in the trocarhousing.

In accordance with another aspect of the disclosure, a surgical systemmay include an adapter assembly and a tip protector. The adapterassembly includes a tubular housing having a distal end portion, and atrocar assembly selectively receivable in the tubular housing. Thetrocar assembly includes a trocar member. The tip protector includes ahousing and first and second locking members coupled to the housing. Thehousing defines a channel therethrough configured for receipt of thetrocar member. The first locking member is configured to selectivelyengage the trocar member to lock the tip protector to the trocar member,and the second locking member is configured to selectively engage thedistal end portion of the tubular housing to lock the tip protector tothe tubular housing.

In aspects, the channel may be a counter bore including a wide channelconfigured for receipt of the distal end portion of the tubular housing,and a narrow channel configured for receipt of the trocar member. Thefirst locking member may extend into the narrow channel and the secondlocking member may extend into the wide channel.

In aspects, the trocar member may define an aperture configured forreceipt of the first locking member, and the distal end portion of thetubular housing may define an aperture configured for receipt of thesecond locking member.

In aspects, the tip protector may include a release button movablycoupled to the housing. The release button may include a first legassociated with the first locking member, and a second leg associatedwith the second locking member. The first and second legs may beconfigured to move the respective first and second locking members outof the respective apertures in response to an actuation of the releasebutton.

In aspects, the adapter assembly may include a first retention pinsupported in the tubular housing. The first retention pin may beconfigured to move relative to the trocar housing between a locked statewith the trocar assembly and an unlocked state with the trocar assembly.The tip protector may be configured to ensure that the first retentionpin is in the locked state with the trocar assembly.

In accordance with yet another aspect of the disclosure, a tip protectorfor use with a circular stapler is provided. The tip protector includesa housing, first and second locking members movably coupled to thehousing, and a release button movably coupled to the housing. Thehousing defines a channel therethrough configured for receipt of atrocar member of an adapter assembly. The first locking member isconfigured to selectively engage the trocar member to lock the tipprotector to the trocar member. The second locking member is configuredto selectively engage a tubular housing of an adapter assembly to lockthe tip protector to the tubular housing. The release button isassociated with each of the first and second locking members, such thatan actuation of the release button moves the first and second lockingmembers outwardly relative to the housing.

In aspects, the channel may be a counter bore including a wide channelconfigured for receipt of the tubular housing, and a narrow channelconfigured for receipt of the trocar member. The first locking membermay extend into the narrow channel and the second locking member mayextend into the wide channel.

In aspects, the release button may include a first leg coupled to thefirst locking member, and a second leg coupled to the second lockingmember. The first and second legs may be configured to simultaneouslymove the respective first and second locking members outwardly relativeto the housing in response to an actuation of the release button.

In aspects, the tip protector may further include a first elongatedspring element and a second elongated spring element. The firstelongated spring element may have a first end portion fixed to a firstside of the housing, and a free, second end portion having the firstlocking member coupled thereto. The second elongated spring element mayhave a first end portion fixed to a second side of the housing, and afree, second end portion having the second locking member coupledthereto. The first and second elongated spring elements may beconfigured to bias the respective first and second locking members froma non-locking position toward a locking position.

In aspects, the second elongated spring element may define a cammingsurface, and the second leg may define a camming surface engaged withthe camming surface of the second elongated spring element, such thatthe second leg moves the second locking member toward the non-lockingposition in response to an actuation of the release button.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the disclosure are described herein with reference to theaccompanying drawings, wherein:

FIG. 1 is a perspective view illustrating a handheld surgical staplinginstrument including a powered handle assembly, an adapter assembly, andan end effector having a reload and an anvil assembly according to anexemplary embodiment of the disclosure;

FIG. 2 is a perspective view, with parts separated, of a trocar assemblyand a tubular housing of the adapter assembly of FIG. 1;

FIG. 3 is an enlarged perspective view illustrating a trocar lockingassembly of the adapter assembly shown in FIG. 1 with a tubular housingof the adapter assembly removed;

FIG. 4 is a perspective view, with parts separated, of the trocarlocking assembly of FIG. 3 including a button, a camming member,retention pins, a support block, and biasing members;

FIG. 5 is a cross-sectional view, taken alone lines 5-5 in FIG. 3,illustrating the trocar locking assembly and the trocar assembly;

FIG. 6 is an enlarged view of the area of detail labeled 6 in FIG. 5;

FIG. 7 is a cross-sectional view, taken along lines 7-7 in FIG. 3,illustrating retention pins of the trocar locking assembly received inopenings in the trocar housing;

FIG. 8 is a longitudinal cross-sectional view illustrating the retentionpins of the trocar locking assembly shown in FIG. 5 engaged with thetrocar housing after testing the retention of the trocar assembly withthe adapter assembly;

FIG. 9 is a side cross-sectional view illustrating the trocar lockingassembly shown in FIG. 5 with the retention pins disengaged from thetrocar assembly;

FIG. 10 is a perspective view illustrating another exemplary embodimentof the disclosed trocar locking assembly;

FIG. 11 is a perspective view illustrating a surgical system includingthe adapter assembly of FIG. 1 and a tip protector;

FIG. 12 is a perspective view illustrating the adapter assembly and thetip protector shown in FIG. 11 assembled to one another;

FIG. 13 is a perspective view of the tip protector of FIG. 11;

FIG. 14 is a front, perspective view illustrating the adapter assemblyshown in FIG. 1 being loaded into the tip protector;

FIG. 15 is a cross-sectional view, taken along lines 15-15 in FIG. 12,illustrating the trocar assembly and the tubular housing fixed withinthe tip protector;

FIG. 16 is a cross-sectional view, taken along lines 16-16 in FIG. 15,illustrating first and second locking members of the tip protectorengaged with the trocar member and the tubular housing, respectively;

FIG. 17 is a perspective view illustrating the tip protector shown inFIG. 16, with the housing removed, and including a release button andfirst and second elongated spring elements; and

FIG. 18 is perspective view of the tip protector of FIG. 17 illustratingthe release button engaged with the second elongate spring element.

DETAILED DESCRIPTION

Embodiments of the disclosure are now described in detail with referenceto the drawings in which like reference numerals designate identical orcorresponding elements in each of the several views. As used herein, theterm “clinician” refers to a doctor, a nurse or any other care providerand may include support personnel. Throughout this description, the term“proximal” will refer to the portion of the device or component thereofthat is closer to the clinician and the term “distal” will refer to theportion of the device or component thereof that is farther from theclinician. Additionally, in the drawings and in the description thatfollows, terms such as front, rear, upper, lower, top, bottom, andsimilar directional terms are used simply for convenience of descriptionand are not intended to limit the disclosure. In the followingdescription, well-known functions or constructions are not described indetail to avoid obscuring the disclosure in unnecessary detail.

The disclosure relates to powered surgical devices having a removabletrocar assembly. The trocar assembly selectively engages an anvilassembly for advancing and retracting the anvil assembly during firingof the surgical device. Components of the trocar assembly may beselectively detached from the surgical device to allow for sterilizationfluids to enter the interior of the surgical device. An improvedmechanism is provided for attaching the trocar assembly and maintainingattachment of the trocar assembly to an adapter assembly of the surgicaldevice until disassembly of the trocar assembly is required.

With reference to FIGS. 1 and 2, a powered surgical device 10, such as,for example, a circular stapler, includes a powered handle assembly 20,which is configured for selective connection with an adapter assembly30, which in turn, is configured for selective connection with an endeffector, such as an annular reload 40. Although generally referred toas being a powered surgical device, it is contemplated that the surgicaldevice 10 may be a manually actuated device and may include variousconfigurations.

The handle assembly 20 includes a handle housing 22 having a lowerhousing portion 24, an intermediate housing portion 26 extending fromand/or supported on a portion of the lower housing portion 24, and anupper housing portion 28 extending from and/or supported on a portion ofthe intermediate housing portion 26. The upper housing portion 28 has adistal portion 32 that is configured to accept a proximal housingportion 34 of the adapter assembly 30.

The adapter assembly 30 includes a tubular housing 36 that includes aproximal end portion 36 a that is configured for operable connection tothe handle assembly 20 and an opposite, distal end portion 36 b that isconfigured for operable connection to the reload 40. The adapterassembly 30 is configured to convert a rotational motion provided by thehandle assembly 20 into axial translation that is useful foradvancing/retracting a trocar member 50 of a trocar assembly 48 that isslidably disposed within the distal end portion 36 b of the tubularhousing 36 of the adapter assembly 30 for firing staples of the reload40.

As best shown in FIG. 1, the reload 40 includes a housing 44 and astaple cartridge 46 fixedly secured to a distal end portion of thehousing 44. The housing 44 is configured for selective connection to thedistal end portion 36 b of the tubular housing 36 of the adapterassembly 30. The reload 40 is configured to fire and form an annulararray of surgical staples against the anvil assembly 42, and to sever orcore a ring of tissue from within tissue sections being anastomosed.

For a detailed description of an exemplary powered surgical staplerincluding an adapter assembly and a reload, reference may be made tocommonly owned U.S. Pat. No. 10,426,468 to Contini et al, titled“Handheld Electromechanical Surgical System,” the entire contents ofwhich being incorporated by reference herein.

With reference to FIG. 2, the trocar assembly 48 of the adapter assembly30 includes a trocar housing 49, a trocar lead screw 52 (FIG. 5), andthe trocar member 50. The trocar housing 49 defines a bore 54 thatextends centrally therethrough, and a pair of opposed openings 56 a, 56b (FIG. 5) that extend through an outer surface of the trocar housing 49and communicate with the bore 54. The trocar lead screw 52 extendsthrough the bore 54 of the trocar housing 49 and is free to rotatewithin the trocar housing 49 during an actuation of the handle assembly20.

The trocar member 50 extends distally beyond the distal end portion 36 bof the tubular housing 36. The trocar member 50 includes a proximal endportion 50 a coupled to the lead screw 52 of the trocar assembly 48, anda distal end portion 50 b configured to releasably engage an anvilassembly 42 (FIG. 1). The lead screw 52 may be threadedly coupled to thetrocar member 50, such that a rotation of the lead screw 52 results inan axial translation of the trocar member 50 in response to an actuationof the handle assembly 20. When the anvil assembly 42 is connected tothe trocar member 50, axial translation of the trocar member 50 in afirst direction results in an opening of the anvil assembly 42 relativeto the reload 40, and axial translation of the trocar member 50 in asecond, opposite direction, results in a closing of the anvil assembly42 relative to the reload 40 to capture tissue therebetween.

With reference to FIGS. 3-7, the adapter assembly 30 includes a trocarlocking assembly 60 including a pair of retention pins 62, 64, a cammingmember 66, and a button 68. Since the first and second retention pins62, 64 are identical or nearly identical to each other, only the firstretention pin 62 will be described in detail.

The retention pins 62, 64 are supported in a support block 70 that isaxially restrained within the tubular housing 36 (FIG. 2) of the adapterassembly 30. The support block 70 defines a longitudinally-extendingbore 72 and transverse bores 73 that communicate with thelongitudinally-extending bore 72. The trocar assembly 48 extends throughthe longitudinally-extending bore 72 of the support block 70. Theretention pins 62, 64 are configured to move within the transverse bores73 in the support block 70 and into the openings 56 a, 56 b of thetrocar housing 49 to selectively lock the trocar housing 49 to thesupport block 70 to lock the trocar assembly 48 within the tubularhousing 36 of the adapter assembly 30.

Each of the retention pins 62, 64 has a first end portion 62 a, 64 aconfigured for receipt in the openings 56 a, 56 b of the trocar housing49, and a second end portion 62 b, 64 b slidably supported within thetransverse bores 73 of the support block 70. The first end portion 62 a,64 a tapers in a direction toward the second end portion 62 b, 64 b. Theopenings 56 a, 56 b of the trocar housing 49 have a correspondingtapered configuration to facilitate retention of the retention pins 62,64 to the trocar housing 49, as will be described. The first end portion62 a, 64 a of each of the retention pins 62, 64 defines chamfered topand bottom edges 74, 76 to ease entry of the retention pins 62, 64 intothe corresponding openings 56 a, 56 b in the trocar housing 49.

The second end portion 62 b, 64 b of each of the retention pins 62, 64defines a stepped hole 78, respectively, through which a respective arm86, 88 of the camming member 66 is received. In particular, and as bestshown in FIG. 5, the stepped hole 78 of the retention pin 62 includes anouter segment 78 a, an inner segment 78 b extending parallel with theouter segment 78 a, and an intermediate segment 78 c connecting andextending perpendicularly between the outer and inner segments 78 a, 78b. The retention pin 62 has first and second opposing camming surfaces82 a, 82 b disposed within the stepped hole 78 of the retention pin 78when the camming member 66 is coupled to the support block 70.

The camming member 66 may be fabricated from a wire and have a generallyU-shaped configuration. In aspects, the camming member 66 may befabricated from other suitable materials and assume other suitableshapes. The camming member 66 includes a backspan 84 and first andsecond arms 86, 88 projecting perpendicularly from respective ends ofthe backspan 84. The backspan 84 of the camming member 66 is disposedbetween the button 68 and the support block 70 or underneath the button68 as viewed in FIG. 5. Since the first and second arms 86, 88 areidentical or nearly identical, only the first arm 86 will be describedin detail.

The first arm 86 of the camming member 66 has a first longitudinalsection 86 a, a second longitudinal section 86 b that is parallel withthe first longitudinal section 86 a, and an intermediate section 86 cinterconnecting the first and second longitudinal sections 86 a, 86 b.The intermediate section 86 c of the arm 86 extends at an oblique anglebetween the first and second longitudinal sections 86 a, 86 b. Theintermediate section 86 c has an outer camming surface 90 a and an innercamming surface 90 b that are configured to interact with the cammingsurfaces 82 a, 82 b of the retention pin 62 during actuation andde-actuation of the button 68, as will be described.

The adapter assembly 30 includes first and second biasing members 92 a,92 b (FIG. 4), such as, for example, leaf springs. In aspects, the firstand second biasing members 92 a, 92 b may be any suitable spring, suchas, for example, a coil spring. The biasing members 92 a, 92 b aredisposed between the support block 70 and the ends of the backspan 84 ofthe camming member 66. The biasing members 92 a, 92 b resiliently biasthe camming member 66 and, in turn, the button 68, toward an unactuatedposition, in which the retention pins 62, 64 are engaged with the trocarhousing 49.

In operation, prior to or after a use of the surgical instrument 10, thesurgical instrument 10 may undergo a sterilization process. To providebetter access to an interior of the surgical instrument 10, the trocarassembly 48 may be disassembled from the tubular housing 36. To removethe trocar assembly 48 from the tubular housing 36 of the adapterassembly 30, the retention pins 62, 64 need to be disengaged from theopenings 56 a, 56 b of the trocar housing 49. The button 68 may becompressed against the resilient bias of the biasing members 92 a, 92 b,thereby moving the arms 86, 88 of the camming member 66 through theintermediate segment 78 c of the stepped hole 78 of each of theretention pins 62, 64. As the arms 86, 88 of the camming member 66 movethrough the stepped hole 78, 88, in the direction indicated by arrow “A”in FIG. 9, the outward camming surface 90 a of the intermediate section86 c of the arms 86, 88 of the camming member 66 engage theinwardly-facing camming surface 82 a of the retention pins 62, 64 tourge the retention pins 62, 64 outwardly in the direction indicated byarrow “B” in FIG. 9. With the retention pins 62, 64 disposed outside ofthe openings 56 a, 56 b in the trocar housing 49, the trocar assembly 48is no longer locked to the tubular housing 36 and may be disengaged fromthe support block 70 by sliding the trocar assembly 48 from thelongitudinally-extending bore 72 of the support block 70.

After sterilization and prior to use of the surgical instrument 10, thetrocar assembly 48 may be loaded into the tubular housing 36 of theadapter assembly 30. To load the trocar assembly 48 into the tubularhousing 36 of the adapter assembly 30, the button 68 of the trocarlocking assembly 60 is compressed to move the first end portion 62 a, 64a of each of the retention pins 62, 64 within the support block 70.While holding the button 68 in the compressed state, the trocar assembly48 is loaded into the tubular housing 36 until the openings 56 a, 56 bin the trocar housing 49 are aligned with the transverse bores 73 of thesupport block 70 and the retention pins 62, 64. With the openings 56 a,56 b of the trocar housing 49 aligned with the retention pins 62, 64,the button 68 is released, whereby the biasing members 92 a, 92 b urgeboth the camming member 66 and the button 68 in the direction indicatedby arrow “C” in FIG. 9. As the camming member 66 moves in the directionindicated by arrow “C,” the inner camming surface 90 b of the cammingmember 66 engages the outwardly-facing camming surface 82 b of theretention pins 62, 64 and urges the first end portion 62 a, 64 a of eachof the retention pins 62, 64 into the respective openings 56 a, 56 b inthe trocar housing 49 to lock the trocar assembly 48 with the adapterassembly 30.

With reference to FIG. 10, the button 68 of the trocar locking assembly60 may include a molded pin 94 extending downwardly therefrom. Themolded pin 94 is configured to interact with a hole 96 of a staple band98. When the trocar assembly 48 is to be removed, the molded pin 94 isfirst aligned with the hole 96 and then the button 68 may be actuated.Prior to alignment of the molded pin 94 and the hole 96, the button 68will be prevented from being actuated. Prior to use of the surgicalinstrument 10, the molded pin 94 is moved out of alignment with the hole96 to prevent inadvertent actuation of the trocar locking assembly 60.For example, once the trocar assembly 48 is inserted and locked to thetubular housing 36, the surgical instrument 10 may be calibrated toconfirm the proper assembly of the trocar assembly 48. Once this isestablished, software stored in the handle assembly 20 (FIG. 1) triggersslight movement of the staple band 98 so that the hole 96 in the stapleband 98 moves out of alignment with the pin 94. This prevents depressionof the button 68, and thus prevents inadvertent un-locking of the trocarassembly 48 at any time after calibration and before the end of theprocedure. Once the procedure is complete, the software can shuffle thestaple band 98 back so that the trocar release button 68 can bedepressed.

With reference to FIGS. 11-18, a surgical system 100 is providedincluding the adapter assembly 30 and a tip protector 200 for betterensuring that the trocar assembly 48 is lockingly engaged with theadapter assembly 30 prior to use. The tip protector 200 may alsofunction as a cover for the trocar assembly 48 when not in use. The tipprotector 200 includes a housing 202 having a generally rectangularshape and a plurality of sides 202 a, 202 b, 202 c, 202 d. In aspects,the housing 202 may assume any suitable shape, such as cylindrical. Thehousing 202 defines a counter bore 204 in a proximal end thereof. Thecounter bore 204 includes a wide channel 204 a (FIG. 14) configured forreceipt of the distal end portion 36 b of the tubular housing 36, and anarrow channel 204 b that extends distally from the wide channel 204 aand is configured for receipt of the trocar member 50 of the trocarassembly 48.

With reference to FIGS. 13, 15, and 16, the tip protector 200 includesfirst and second biasing members 206, 208, such as, for example, firstand second elongated spring elements coupled to adjacent first andsecond sides 202 a, 202 b of the housing 202. In aspects, the biasingmembers 206, 208 may be plate-like leaf springs that are supported incantilevered fashion to the housing 202 of the tip protector 200. Thefirst biasing member 206 has a first end 206 a fixed to the housing 202,and a second end 206 b free to flex relative to the first end 206 a. Thesecond biasing member 208 has a first end 208 a fixed to the housing202, and a second end 208 b free to flex relative to the first end 208a.

With reference to FIGS. 14-16, the tip protector 200 has first andsecond locking members 210, 212 movably coupled to the housing 202 ofthe tip protector 202. In particular, the first locking member 210 isassociated with (e.g., coupled to) the second end 206 b of the firstbiasing member 206, and the second locking member 212 is associated with(e.g., coupled to) the second end 208 b of the second biasing member208. The first locking member 210 may assume a block shape and have anengaging end 214 configured to selectively engage an aperture 102defined in the trocar member 50. The second locking member 212 mayassume a block shape and have a chamfered, engaging end 218 configuredto selectively engage an aperture 104 defined in the distal end portion36 b of the tubular housing 36. In aspects, the first and second lockingmembers 210, 212 may assume any suitable shape, such as, for example,rounded, elongated, etc. The first biasing member 206 biases theengaging end 214 of the first locking member 210 into the narrow channel204 a of the counter bore 204, and the second biasing member 208 biasesthe engaging end 218 of the second locking member 212 into the widechannel 204 a of the counter bore 204.

With reference to FIGS. 17 and 18, the tip protector 200 includes arelease button 220 movably supported in the side 202 c of the housing202 and functions to simultaneously disengage the first locking member210 from the trocar member 50 and the second locking member 212 from thetubular housing 36 b of the adapter assembly 30. The release button 220includes a surface projection 226 extending outwardly from the side 202c of the housing 202 and first and second legs 222, 224 extendingperpendicularly from the surface projection 226 into the housing 202.The surface projection 226 is configured to be acted on by a user. Thefirst leg 222 has an end portion 228 engaged with the second end 206 bof the first biasing member 206. The second leg 224 of the releasebutton 220 has an oblique, camming surface 230 engaged with an obliquecamming surface 232 attached to the second end 208 b of the secondbiasing member 208.

In operation, to better ensure that the trocar assembly 48 is properlyloaded in the tubular housing 36 of the adapter assembly 30, the tipprotector 200 may be utilized. The tip protector 200 is positioned overthe trocar member 50, whereby the tip of the trocar member 50 passesthrough the narrow channel 204 b of the tip protector 200 and engagesthe engagement surface 214 of the first locking member 210 to urge thefirst locking member 210 outwardly relative to the housing 202. Movementof the tip protector 200 proximally relative to the adapter assembly 36and/or distal movement of the adapter assembly 36 relative to the tipprotector 200 is continued, whereby the distal end portion 36 b of thetubular housing 36 enters the wide channel 204 a of the tip protector200 and engages the second locking member 212 of the tip protector 200.Due to the engaging end 218 of the second locking member 212 beingchamfered, advancement of the tubular housing 36 into the wide channel204 a urges the second locking member 212 outwardly.

Advancement of the adapter assembly 30 through the tip protector 200 iscontinued until the first locking member 210 of the tip protector 200 isaligned with the aperture 102 in the trocar member 50, and the secondlocking member 212 of the tip protector 200 is aligned with the aperture104 in the tubular housing 36. The first biasing member 206 biases thefirst locking member 210 into engagement with the aperture 102 in thetrocar member 50, and the second biasing member 208 biases the secondlocking member 212 into engagement with the aperture 104 in the tubularhousing 36. As such, the tip protector 200 is simultaneously locked(e.g., axially restrained) with the trocar member 50 of the trocarassembly 48 and the tubular housing 36 of the adapter assembly 30.

With the tip protector 200 fixed to the trocar assembly 48 and thetubular housing 36, to ensure that the trocar assembly 48 is properlyengaged with the adapter assembly 30, the handle assembly 20 (FIG. 1) isactuated. Actuation of the handle assembly 20 imparts a rotational forceon the trocar screw 52 of the trocar assembly 48, which exerts adistally-oriented axial force on the trocar member 50. However, sincethe tip protector 200 is fixed to the trocar member 50 and the tubularhousing 36, rotational movement of the trocar screw 52 will not resultin axial movement of the trocar member 50. In the scenario where thetrocar assembly 48 is not properly engaged with the tubular housing 36,the distally-oriented axial force exerted on the trocar member 50 by theactuated trocar screw 52 drives the trocar screw 52 proximally relativeto the trocar member 50 rather than advance the trocar member 50 due tothe trocar member 50 being axially fixed with the tip protector 200. Thetrocar screw 50 retracts, along with the trocar housing 49 (FIGS. 7 and8), until the retraction pins 62, 64 (FIGS. 7 and 8) of the trocarlocking assembly 60 are aligned with and ultimately engage thecorresponding openings 56 a, 56 b in the trocar housing 49 to lockinglyengage the trocar assembly 48 with the adapter assembly 30.

Once locked, the engagement of the trocar assembly 48 with the adapterassembly 30 may be tested by actuating the handle assembly 20. If aselected force is achieved (e.g., about 10-100 pounds), then the trocarassembly 48 is determined to be properly engaged with the adapterassembly 30. During this test, the trocar housing 49 may be moved, suchthat the tapered first end portion 62 a, 64 a of each of the retentionpins 62, 64 frictionally engage the correspondingly tapered surface thatdefines the openings 56 a, 56 b of the trocar housing 49, as shown inFIG. 8. With this engagement, a greater force will be required to movethe retention pins 62, 64 out of the openings 56 a, 56 b of the trocarhousing 49. Therefore, inadvertent actuation of the button 68 (FIG. 3)of the adapter assembly 30 will not generate enough force to overcomefrictional engagement between retention pins 62, 64 and the openings 56a, 56 b of the trocar housing 50.

With reference to FIGS. 16-18, after it is determined that the trocarassembly 48 is properly engaged with the adapter assembly 30, therelease button 220 of the tip protector 200 may be compressed. Anactuation of the release button 220 moves the first leg 222 of therelease button 220, which urges the second end 206 b of the firstbiasing member 206 and the attached first locking member 210 outwardly.The first locking member 210 disengages the aperture 102 in the trocarmember 50 to release the tip protector 200 from the trocar assembly 48.An actuation of the release button 220 also moves the second leg 224 ofthe release button 220 relative to the second biasing member 208. Themovement of the second leg 224 of the release button 220 slides thecamming surface 230 of the second leg 224 along the camming surface 232of the second biasing member 208 to pivot the second end 208 b of thesecond biasing member 208 and the attached second locking member 212outwardly and out of engagement with the aperture 104 in the distal endportion 36 b of the tubular housing 36. In this way, a single actuationof the release button 220 results in a disengagement of the tipprotector 200 from both the trocar assembly 48 and the adapter assembly30.

It will be understood that various modifications may be made to theembodiments of the disclosed adapter assemblies. Therefore, the abovedescription should not be construed as limiting, but merely asexemplifications of embodiments. Those skilled in the art will envisionother modifications within the scope and spirit of the disclosure.

1. (canceled)
 2. A surgical system, comprising an adapter assemblyincluding: a tubular housing having a distal end portion; and a trocarassembly selectively receivable in the tubular housing and having atrocar member; and a tip protector including: a housing defining achannel longitudinally therethrough configured for receipt of the trocarmember; a first locking member coupled to the housing and configured toselectively engage the trocar member to lock the tip protector to thetrocar member; and a second locking member coupled to the housing andconfigured to selectively engage the distal end portion of the tubularhousing to lock the tip protector to the tubular housing.
 3. Thesurgical system according to claim 2, wherein the channel is acounterbore including a wide channel configured for receipt of thedistal end portion of the tubular housing, and a narrow channelconfigured for receipt of the trocar member.
 4. The surgical systemaccording to claim 3, wherein the first locking member extends into thenarrow channel and the second locking member extends into the widechannel.
 5. The surgical system according to claim 4, wherein the firstlocking member is configured to move relative to the housing in responseto the trocar member being received in the narrow channel, and thesecond locking member is configured to move relative to the housing inresponse to the tubular housing being received in the wide channel. 6.The surgical system according to claim 2, wherein the first lockingmember is spaced distally from the second locking member.
 7. Thesurgical system according to claim 6, wherein the first and secondlocking members are offset laterally relative to one another.
 8. Thesurgical system according to claim 2, wherein the trocar member definesan aperture configured for receipt of the first locking member, and thedistal end portion of the tubular housing defines an aperture configuredfor receipt of the second locking member.
 9. The surgical systemaccording to claim 8, wherein the tip protector includes a releasebutton movably coupled to the housing and including: a first legassociated with the first locking member; and a second leg associatedwith the second locking member, the first and second legs beingconfigured to move the respective first and second locking members outof the respective apertures in response to an actuation of the releasebutton.
 10. The surgical system according to claim 2, wherein the trocarmember has a distal end configured to be concealed within the channel ofthe housing of the tip protector when the tip protector is coupled tothe adapter assembly.
 11. The surgical system according to claim 2,wherein the first and second locking members are configured to axiallyfix the trocar member to the tubular housing when the tip protector iscoupled to the adapter assembly.
 12. The surgical system according toclaim 2, wherein the tip protector is configured to detachably couple tothe adapter assembly.
 13. The surgical system according to claim 2,wherein the adapter assembly includes a first retention pin supported inthe tubular housing, the first retention pin being configured to moverelative to the trocar housing between a locked state with the trocarhousing and an unlocked state with the trocar housing, the tip protectorbeing configured to ensure that the first retention pin is in the lockedstate with the trocar housing.
 14. A tip protector for use with acircular stapler, the tip protector comprising: a housing defining achannel therethrough configured for receipt of a trocar member; a firstlocking member movably coupled to the housing and configured toselectively engage the trocar member to lock the tip protector to thetrocar member; and a second locking member movably coupled to thehousing and configured to selectively engage a tubular housing of anadapter assembly to lock the tip protector to the tubular housing. 15.The tip protector according to claim 14, wherein the channel is acounterbore including a wide channel configured for receipt of thetubular housing, and a narrow channel configured for receipt of thetrocar member, the first locking member extending into the narrowchannel and the second locking member extending into the wide channel,the narrow channel being configured to house a distal end of the trocarmember therein.
 16. The tip protector according to claim 14, furthercomprising a release button movably coupled to the housing andassociated with each of the first and second locking members, such thatan actuation of the release button moves the first and second lockingmembers outwardly to detach the first and second locking members fromthe respective trocar member and the tubular housing.
 17. The tipprotector according to claim 16, wherein the release button includes: afirst leg coupled to the first locking member; and a second leg coupledto the second locking member, the first and second legs being configuredto simultaneously move the respective first and second locking membersoutwardly in response to an actuation of the release button.
 18. The tipprotector according to claim 17, further comprising: a first elongatedspring element having a first end portion fixed to a first side of thehousing, and a free, second end portion having the first locking membercoupled thereto; and a second elongated spring element having a firstend portion fixed to a second side of the housing, and a free, secondend portion having the second locking member coupled thereto, whereinthe first and second elongated spring elements are configured to biasthe respective first and second locking members from a non-lockingposition toward a locking position.
 19. The tip protector according toclaim 18, wherein the second elongated spring element defines a cammingsurface, and the second leg defines a camming surface engaged with thecamming surface of the second elongated spring element, such that thesecond leg moves the second locking member toward the non-lockingposition in response to an actuation of the release button.
 20. A methodof locking a trocar assembly to an adapter assembly of a surgicalinstrument, the method comprising: positioning a tip protector over atrocar member of the trocar assembly and a tubular housing of theadapter assembly; selectively locking the trocar member of the trocarassembly and the tubular housing to the tip protector; driving a trocarscrew of the trocar assembly while the trocar member and the tubularhousing are locked to the tip protector to lock the trocar assembly tothe tubular housing.
 21. The method according to claim 20, whereindriving the trocar screw includes retracting the trocar screw and atrocar housing of the trocar assembly relative to the trocar member,whereby a corresponding pair of openings in the trocar housing receive apair of retention pins of the adapter assembly to axially fix the trocarassembly to the tubular housing.